Re: What happens if tuple queue is full - Mailing list pgsql-hackers

From Haribabu Kommi
Subject Re: What happens if tuple queue is full
Date
Msg-id CAJrrPGdam9RZodEYB5xowXT6UCXQ77O9ZwTCydqiW=WWs1XqGA@mail.gmail.com
Whole thread Raw
In response to What happens if tuple queue is full  (Tatsuo Ishii <ishii@postgresql.org>)
Responses Re: What happens if tuple queue is full  (Tatsuo Ishii <ishii@postgresql.org>)
List pgsql-hackers
On Wed, Jul 6, 2016 at 10:57 AM, Tatsuo Ishii <ishii@postgresql.org> wrote:
> Hi,
>
> Does anybody know what will happen if tuple queue is full, which is
> used by the parallel leader and workers? In my understanding memory
> used for the queue is a dynamic shared memory and it could be full.

The queue can gets full in the case where the leader is processing is slow
than the worker is producing tuples. In those scenarios, the worker waits
until the the queue gets empty to place the new satisfied record.The worker
gets awaken whenever the leader finishes reading the data from queue.


Regards,
Hari Babu
Fujitsu Australia



pgsql-hackers by date:

Previous
From: Tatsuo Ishii
Date:
Subject: What happens if tuple queue is full
Next
From: Masahiko Sawada
Date:
Subject: Fix typo in jsonb.c